As a flow path for discharging offgas and water in a porous body of a fuel cell, there is a discharge flow path that employs a pectinated member (see Patent Document 1).
There are also techniques for separating and discharging offgas and water, including a technique of arranging a water repellent member and a water immersible member in a downstream part of a porous body, a technique of enlarging the cross-sectional area of a flow path in a cathode side downstream part to reduce a flow rate and thereby cause water to be accumulated therein, and a technique of providing a small-diameter hole as a water flow path and a large-diameter hole as a gas flow path in a porous body (see Patent Documents 2, 3, and 4).
Patent Document 1: Japanese Unexamined Patent Publication No. H07-326373
Patent Document 2: Japanese Unexamined Patent Publication No. 2000-149966
Patent Document 3: Japanese Unexamined Patent Publication No. 2005-285636
Patent Document 4: Japanese Unexamined Patent Publication No. H07-320753